Container

ABSTRACT

A container has side walls of substantially equal height and a lid. The container is of corrugated material. The lid has a central panel and side panels attached to the central panel by score lines. The lid is of fiberboard material. The lid side panels are glued to the container side walls.

This is directed to a shipping container and the blanks for thecontainer.

One type of container used as a shipping container is a regular slottedcontainer known as an RSC. It is the blank 10 shown in FIG. 1 and thecontainer 11 shown in FIG. 2. It has side walls 12 and 13 and end walls14 and 15 attached to each other by score lines. An attachment panel 16is attached to side wall 12 by a score line. The attachment panel 16 isglued to end panel 15 in the finished container. Closure flaps 17, 18,19 and 20 are attached by score lines on the upper and lower edges ofthe side walls 12 and 13, and closure flaps 21, 22, 23 and 24 areattached to the upper and lower edges of end walls 14 and 15.

In forming the container for use, the container is opened from alay-flat position and the lower closure flaps 19, 20, 23 and 24 arefolded in and fastened together. The container is filled and the upperclosure flaps 17, 18, 21 and 22 are folded in and fastened together. Thetop and bottom end panel closure flaps are usually covered by the sidepanel closure flaps.

For storage and transport the containers are stacked several high sostacking strength is necessary. A container should hold the containersabove it without transferring the load to the contained product and itsdeformation should be minimal.

A corrugated container has a wall made of central flutes made ofcorrugating medium held in place by outer liners glued to the flutes.The flutes will normally extend vertically in the filled container toprovide stacking strength. The actual stacking strength will depend onthe size of the flute and the weight of the corrugating medium and theweight of the liners.

There are several size flutes. Some flute sizes are A flute which has 36flutes per lineal flute and is 3/16 inch from flute tip to flute tip; Bflute which has 51 flutes per lineal flute and is 3/32 inch from flutetip to flute tip; C flute which has 39 to 42 flutes per lineal flute andis 9/64 inch from flute tip to flute tip; and E flute which has 96flutes per lineal flute and is 3/64 inch from flute tip to flute tip.

Basis weights for corrugating medium are from 16 to 40 pounds perthousand square feet. Basis weights for liner are from 20 to 96 perthousand square feet.

It should be understood that the higher basis weights increase the costof a container.

The stacking strength may also be increased by using multiwall board.The board may be double wall with an external liner, a corrugatedmedium, a central liner, another corrugated medium and another outerliner. The board may be triple wall with an outer liner, a corrugatingmedium, an inner liner, a second corrugating medium, another innerliner, another corrugating medium and another external liner. The mediummay be any flute size and the weights of the various elements may be thesame or different. Again, the addition of the additional materialincreases the cost of the container.

After much research, and many trials it has been discovered that thereis a simple way of increasing the stacking strength of a containerwithout increasing the basis weight of the various elements of thecontainer, or increasing the number of walls of the container.

FIG. 1 is a top plan view of a prior art regular slotted container.

FIG. 2 is an isometric view of a container formed from the blank of FIG.1.

FIGS. 3-4 are top plan views of blanks for an embodiment of the presentinvention.

FIG. 5 is an isometric view of a container made from the blanks of FIGS.3-4.

FIG. 6 is a top plan view a blank for an embodiment of the presentinvention. It is the bottom lid of a double cover container.

The blank 30 for the container lid has a central panel 31 and four sidepanels 32 attached to the four sides of the central panel 31 by scorelines 33. There are no tabs attached to the side panels 32. The blank ismade of solid fiberboard having a basis weight of 50 to 400 pound perthousand square feet.

The blank 40 for the container body has side walls 41, 42, 43 and 44 andattachment panel 45 connected by score lines 46, 47, 48 and 49. Theattachment panel 45 is attached to the outer edge of side wall 41.

The body usually is formed into a lay flat condition at the corrugatedplant by gluing the attachment panel 45 to the outer edge of the innerside of side panel 41.

At the point of use the container can be formed by hand or by machine.

In the method of forming the container, the side walls 41,42, 43 and 44will be squared so that two opposing side are substantially parallel.The walls will form a rectangular tube. The score lines of the lid 30will be aligned with the outside of the side walls of the body. Gluewill be placed on the panels 32. The glue may be placed on the panels 32while the lid is being moved into position for the alignment step,during the alignment step, the seating step or after the body and lidhave been aligned and seated. The panels will then be folded up aroundthe side walls and adhered to the side walls.

In one embodiment the side walls 81′, 82′, 83′ and 84′ will be squaredso that two opposing sides are substantially parallel. The side wallswill form a rectangular tube. The tube will be horizontal. The lid 100will be moved vertically into alignment with the body. Glue will beplaced on the lid side panels during that movement. A mandrel will beinserted into the container body and move the body toward the lid untilthe side walls are seated on the lid and the sides of the side walls arealigned with the lid score lines. The mandrel will carry the body andlid will through a die cavity which will bend the lid panels aroundtheir score lines and place the lid panels against the container sidewalls, holding the lid panels against the side wall long enough toadhere the lid panels to the side walls.

The container will be filled with product and a lid placed on the top ofthe container. The top lid may have the design shown in FIG. 3 or mayhave the design shown in FIG. 6. The blank 50 for a container upper lidhas a central panel 51 and four side panels 52 attached to the foursides of the central panel 51 by score lines 53. There are tabs 54attached to the sides of panels 52. In forming the lid the tabs 54 arebent upwardly until they are perpendicular to the side panels 52. Theside panels 52 are bent upwardly until they are perpendicular to thecentral panel 51. The tabs 54 are attached to the adjacent side panel52. The blank is also made of solid fiberboard.

The upper lid may be loose, or the lid may be attached to the container.

The container and lid are shown as being four sided. The container andlid may have any number of sides. In any configuration the side walls ofthe container will fit into the crushed area of the upper and lowerlids.

Embodiments of the present invention have been tested for stackingstrength and for side deformation. In the tests the containers werefilled with tennis balls.

In one test an embodiment was compared to an RSC. Both containers weresingle wall using a 26 pound C flute corrugated medium and a 35 poundliner glued to both sides of the flutes. The containers were 24 incheslong, 15 inches wide and 15 inches deep. The maximum compression loadfor the RSC was 600 pounds. The maximum compression load for thecontainer with a 90 pound fibreboard glued lid was 1390 pounds. Thedeformation of the side walls at maximum load for the RSC was 0.34inches. The deformation of the side walls of the container with a 90pound fibreboard glued lid at maximum load was 0.1 inches.

In another test an embodiment was compared to an RSC. Both containerswere double wall using a 35 pound liner glued to one side of a 26 poundB flute corrugated medium, a 35 pound center liner glued to the fluteson both sides, a 26 pound B flute corrugated medium and a 35 pound linerglued to the those flutes. The containers were 24 inches long, 15 incheswide and 15 inches deep. The maximum compression load for the RSC was1500 pounds. The maximum compression load for the container with a 90pound fibreboard glued lid was 3000 pounds. The average deformation ofthe side walls at maximum load for the RSC was 0.57 inches. Thedeformation of the side walls of the container with a 90 poundfibreboard glued lid at maximum load was 0.13 inches.

While embodiments of the invention has been illustrated and described,it will be appreciated that various changes can be made therein withoutdeparting from the spirit and scope of the invention.

1. A container comprising a container having upstanding side walls ofsubstantially equal height, the side walls being of corrugated material,a top and bottom lid for the container, the lids being of solid fibermaterial, the lids having a central panel and side panels attached tothe central panel by score lines, the bottom lid being attached to oneend of the container side walls, the bottom lid side panels being gluedto the container side walls.
 2. The container of claim 1 wherein thereare no tabs on the side edges of the bottom lid side panels.
 3. Thecontainer of claim 1 wherein the container side walls each have at leastone layer of corrugated material and liner material attached on bothsides of the corrugated material.
 4. The container of claim 3 whereinthe lid is has a basis weight of 50 to 400 pounds per thousand squarefeet.
 5. The container of claim 3 wherein the side walls are single wallcorrugated with one corrugated layer and a liner attached to each sideof the corrugated layer.
 6. The container of claim 5 wherein the lid ishas a basis weight of 50 to 400 pounds per thousand square feet.
 7. Thecontainer of claim 3 wherein the side walls are multi-wall corrugatedwith at least two corrugated layers and a liner attached to the outerside of each corrugated layer, and a liner between the corrugatedlayers.
 8. The container of claim 7 wherein the lid is has a basisweight of 50 to 400 pounds per thousand square feet.
 9. The container ofclaim 1 wherein there are no tabs on the side edges of the top lid sidepanels and the top panels are glued to the side walls of the container.